Bridge construction.



No. 747,511. A VPATENTED DEG. 22, 190s. J; ToMLINsoN. BRIDGECONSTRUCTION.

y APPLICATION FILED JUNE 26, 1,903. yNo MODEL.

WWA/VNV we nonms PsTzws co, pHoro-mwa, Msnnnrou. n. c.

- as shown in Fig. 1.

Nav-17,511.

Patented December 22, 1903.

PATENT OFFICE.'

JOSEPH TOMLINSON, OF CEDAR RAPIDS, IOWA.v

BRIDGE CONSTRUCTION.

SPECIFICATION forming part of Letters Patent No. 747,511, dated December22, 1903.

Application filed June 26,1903. Serial No. 163,253. (No model.)

To all whom, t may concern:

Be it known that I, JOSEPH ToMLINsoN, a citizen of the United States,residing at Cedar Rapids, in the county of Linn and State of Iowa, haveinvented certain new and useful Improvements in Bridge Construction, ofwhich the following is a specification.

This invention relates to cantaliver suspension-bridges supported onsteel chains or wire cables and the like in which the suspendedstructure is constructed to form a rigid stretcher between the ends ofthe cables orv chains. The whole being formed of steel 0r iron willexpand and contract equally. with the cables.

The primary object of my invention is to construct the suspended part ofthe structure in the strongest possible manner, eliminating as much aspossible all weighty materials that do not increase its strength,rigidity, and

durability.

The nature of the invention will fully appear from the description andclaims following, reference being had to the accompanying drawings, inwhich- Figure 1 is a side elevation of a cantaliver suspension-bridgeconstructed in accordance with my invention. Fig. 2 isa fragmentary planview of the Hoor or deck, showing its general construction, the rails inthis case being` placed midway of the longitudinal girders. railsplaceddirectly over the longitudinal girders. Fig. 4. shows a transversegirder uniting the chords of the main trusses and supporting thelongitudinal girders, inV this case three in number. Fig. 5 is asimilar. view, but showing two instead of three lon-- gitudinal girders.Fig. 6 is a framentary plan view showing the manner of mounting therailway-rails on the bridgeiioor when placed between the girders.l Figs.7 and 8 are sections taken in the lines a b and c d, respectively.

In carrying out my invention in practice the main stiening-trusses aremade of great depth, with the bracing forminglong panels, The transversegirders B, uniting the chords of the main trusses A, have considerabledepth and are both very light and very strong, so as to amply supportFig. 3 is a similar view, but with the.

the longitudinal girders O, the floor D, tracks E, and moving loadspassing over t-hem.

The longitudinal girders extending the whole length of the structurehave depth and strength to support and convey the moving loads1 to thetransverse girders. Their upper chords are formed with angle-irons O' tounite them by rivets with the lattice-flooring, which serves to,holdthem' straight and adds considerably to their compressive strength.

YIn Fig. 4E three longitudinal girders are shown placed far-enough apartto allow the railway-rails to be mounted on the latticefloor above andbetween them. By this construction the spring or slight yield to theimpact of passing loads preventsinjurious jars that are usually avoidedby the use of timber ties. 1 I

-In Fig. 5 two longitudinal girders are shown, and these are'placeddirectly under the rails E and guard-rails F, which latter may beriveted through the lattice-bars of the door to the angle-irons of thetop chords of the girders. Y

The tloor or deck ot' the bridgeis formed of two layers of steel or ironflat bars long enough to unite the chords of the main trusses andarranged in opposite diagonal lines, as shown. These bars D are securelyriveted to the upper angle-irons of the chords to corresponding parts ofthe girders and to each other at every intersection. The union of bothupper edges of the chords ltaires the place ot' plates or lacing. Thisconstruction, involving comparatively little weight-in the tlooring,Vforms a system of lattice-bracing from side to side and the wholelength of the structure and adds very greatly to its compressivestrength.

In securing the rails and guard-rails tothe Alattice-flooring midway ofthe longitudinal girders the guard-rails areA riveted to thelattice-barsand add their own stiffness to the compressive strength ofthe structurel On the rabbeted inner edges of these guard-rails are setthe railway-rails and are held securely in place by bolts and clips, asindicated in Fig. 2, or by continuous clamp-bars K and bolts, as shownin Figs. 6 and 8; In the case of the latter construction the clamp-barsmay be riveted to the rail-flanges and the latter IOO in turn bolted tothe guard-rails and through the lattice-bars, as shown.

In the case of a foot-bridge channel-bars would take the place of therails and guardrails shown, beingriveted to the lattice-bars at asuitable distance apart to take the wheels of vehicles. The channel-barsthus add to the compressive strength in the Ysame manner as do the railsand guard-rails and allow the planking to be thinner and lighter thanwould be required for the concentrated weight of loaded wheels.

The rails are laid on the bridge with closelyabutting ends, which aresecured by fishplates with Haring bottom anges L, secu rely bolted tothe iioor of the bridge. The rails thus become component parts of thebridge and take their part of the compression. No provision need be madefor the expansion and contraction of the rails, (as by slotting theish-plate bolt-holes,) since the' rails expand and con tract equallywith all other parts ofthe bridge.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

1. In a bridge or the like structure, a ioor or deck composed of fiatsteel or iron bars placed obliquely in opposite directions, riveted toeach other at the intersections, and to the main trusses and thelongitudinal and transverse girders, substantially as and for thepurpose set forth.

2. In a railway-bridge, the combination with the rails, of a Hoor ordeck of diagonallycrossing lattice-bars of steel or iron riveted to thebridge trusses and girders, and riveted or bolted to the rails,substantially as described.

3. In a bridge having trusses and girders, substantial] y as described,a lattice-Hoor composed of obliquely-crossing fiat bars of steel or ironriveted to said tiusses and girders and to each other at theintersections, and rails secured to the lattice-work between thegirders, substantially as and for the purpose set forth.

4. In a railway-bridge, the combination with the fioor composed ofobliquely-crossi'ng lattice-bars of steel or iron riveted to the trussesand girders, of rails having clampbars riveted to their bottom ianges,guardrails rabbeted to take the edges of said danges, and riveted to thelattice-Work, the clampbars being held by bolts or rivets passing`through them, the guard-rails and said lattice.

5. In a railway-bridge, the combination with a steel or ironlattice-door riveted to the trusses and girders, of guard-rails rivetedto the lattice, and rabbeted to take the sides of the rails, clamp-barsextending between the fish-plates, and tish-plates with extended lateralflanges, said clamp-bars and fish-plates being?` bolted through theguard-rails and lattice-iioor, substantially as described.

In testimony whereof I aflx my signature in presence of two witnesses.

JOSEPH TOMLINSON.

Witnesses:

F. J. KUBICEK, J. M. ST. JOHN.

